Expression: split Expression.h to ExpressionParser.h

Split Expression details into a separate header to reduce recompilation
time on changes.

src/Mod/Sketcher/App/PropertyConstraintList.cpp

@@ -36,6 +36,7 @@
 #include <Base/QuantityPy.h>
 #include <App/ObjectIdentifier.h>
 #include <App/DocumentObject.h>
+#include <App/ExpressionParser.h>
 
 #include "PropertyConstraintList.h"
 #include "ConstraintPy.h"

src/Mod/Spreadsheet/App/Cell.cpp

@@ -38,7 +38,7 @@
 #include <Base/UnitsApi.h>
 #include <Base/Writer.h>
 #include <Base/Console.h>
-#include <App/Expression.h>
+#include <App/ExpressionParser.h>
 #include "Sheet.h"
 #include <iomanip>
 

src/Mod/Spreadsheet/App/PropertySheet.cpp

@@ -43,6 +43,7 @@
 #include "Utils.h"
 #include <PropertySheetPy.h>
 #include <App/ExpressionVisitors.h>
+#include <App/ExpressionParser.h>
 FC_LOG_LEVEL_INIT("Spreadsheet", true, true)
 
 using namespace App;

src/Mod/Spreadsheet/App/Sheet.cpp

@@ -35,6 +35,7 @@
 #include <App/Document.h>
 #include <App/DynamicProperty.h>
 #include <App/FeaturePythonPyImp.h>
+#include <App/ExpressionParser.h>
 #include <Base/Exception.h>
 #include <Base/FileInfo.h>
 #include <Base/Placement.h>

src/Mod/Spreadsheet/Gui/PropertiesDialog.cpp

@@ -26,6 +26,7 @@
 #include <Base/Tools.h>
 #include <App/Range.h>
 #include <App/Document.h>
+#include <App/ExpressionParser.h>
 #include <Gui/Command.h>
 #include "ui_PropertiesDialog.h"